Apparatus for forming tubes



June 9, 1936. IVERSEN ET AL APPARATUS FOR FORMING TUBES Filed Dec. 2,1952 7 sheets -sixeet l J m I June 9, 1936" I L. IVERSEN ET AL 2,043,665

APPARATUS FOR FORMING TUBES Filed Dec. 2, 1932 7 Sheets-Sheet 2 N NINVENTORS Y June 9, 1936- L. IVERSEN ET AL 2,043,655

APPARATUS FOR FORMING TUBES Filed Dec. 2, 1932 7 Sheets-Sheet 5INVENTORS June 9, 1936.

L IVERSEN ET AL APPARATUS FdR FORMING TUBES iled Dec. 2, 1952 7Sheets-Sheet 4 mm 313:: r

; )VENTORS June 9, 1935- L.-I\IIERSEN ET AL 2,043,655

APPARATUS FOR FORMING TUBES 7 Sheets-Sheet 7 Filed Dec. 2, 1932INVENTORS J & 2%

Patented June 9, 1936 UNITED STATES PATENT OFFICE- FOR FORMING TUBESLorena Iversen, Pittsburgh, and Charles L. Raislg, Coraopolis, Pa.,a'ssignors to 'Mesta Machine Company, Homestead, Pa., a corporation ofPc'nnsyl The present invention relates broadly to the art of metalworking, and more particularly to metal bending and shaping wherebysubstantially flat sheets or plates may be formed into tubes,1

pipes and the like. V In this connection the term tubes will hereinafterbe utilized in its generic sense as definitive of shapes having thegeneral characteristics in question.

At the present time, there are two general methods in vogue for theforming up, usually cold, of long sheets or plates into tubular shape.In accordance with one of these methods the flat material is fed in adirection generally parallel to its longitudinal axis through asuccession of roll stands providing passes of successively changingcontour such that the edges are first curled up slightly to provide achannel shaped section, and thenthe curling up operation completed.While suciaa forming means may be satisfactorily utilized foraccomplishing the intended purposes,

the number of stands required in order to complete the forming upoperation represents a very large investment. The spacing incident tothe location of the stands also extends the complete- .unit to such alength that a comparatively large.

to the control of the edges in-o'rderto prevent twisting or deformationthereof, have been such as to prevent any extended use of formers ofthis yp t In accordance with the present invention, there is provided aforming apparatus, which may be of a length such as to properlyaccommodate sheets or plates to be formed into tubes, and effectiveforproducing such a forming operation by grad- V uaily curving theparent metal around a mandrel,

anrlaccurately controlling the forming operation during theentireprocess. In this manner it is possible to produce an accuratelyformed tube, free from camber, and characterized by a seam line betweenthe meeting edges which extends in a truly longitudinal direction anddoes not extend spirally of the blank. Such a blank is admirably suitedto presentday welding methods, and facilitates the performance of a seamwelding operation diagrammatically, a preferred embodiment of thepresent invention. In the drawings:--- Figure 1 is a top plan view of anapparatus in accordance with our invention; v

Figure 2 is a top plan view of a portion of the apparatus illustrated inFigure 1;

Figure 3 is a detail view partly in section and partly in elevation ofthe initial sizing pass;

Figure 4 is a transverse sectional view partly in elevation through oneof the forming units;

Figure 5 is a side elevational view partly broken away and partly insection of the forming unit of Figure 4;

Figure 6 is a view generally similar to Figure 4, but illustrating theformer unit in opened condi- Figures '7 to 13 both inclusive arediagrammatic views showing successive operations incident to theformation of a tube;

Figure 14 is a view partly in section and partly in elevation of thesizing pass; and

Figure 15 is a detail sectional view, on an enlarged scale, along theline XVXV of Figure 2, looking in the direction of the arrows.

Referring to Figure 1, a metal forming or shaping apparatus inaccordance with the present invention includes a conveyor unitconveniently in the form of a roll table 2 of suitable construction andincluding a plurality of rolls adapted to be driven in. synchronism foreffecting a feeding movement therealong of material placed thereon.

In actual practice, the rolls are driven in such direction as to effecta feeding movement in the direction of thearrow 3 of Figure 1.

Cooperating with thewreceiving end 4 'of the conveying unit 2 is a metalforming unit 5. This metal forming unit is illustrated in detail inFigure 3 as comprising a roll stand 6 containing upper and lower rolls 1providing a pass 8 therebetween shaped to accommodate a flat sheet orplate to be formed into a tube. v

In line with the pass 8, and constituting edge engaging'and formingmeans for such a sheet or plate, are edge forming rolls 9 carried insuitable bearings I 0 adapted to be adjusted inwardly or outwardly bymeans of adjusting screws II. In this manner, it is possible to vary theposition of the edge forming means 9 to cooperate with sheets .or platesof difierent widths. The pressure exerted by the rolls 1 through themedium 01' springs l2 may be increased or decreased at will by properoperation of spring adjusting screws l 4. In like manner, the positionof the rolls and the width ofthe pass may be varied through a suitedges,is also eifective'for insuring uniform overe11 width throughout thelength of the sheet or 'plate being passed through the forming unit.

The rolls I are adapted to be driven in any desired manner, as by amotor l1 and gear stand ID, the direction of rotation of the rolls beingsuch that as the material is flattened, brought to "width and the edgestrued, it passes onto the conveying unit 2. The conveying unit being inoperation, the material is conveyed to a point adjacent the left handend of the conveyor in front of a series of curling units l9, the numberof which may be varied in accordance with the length of the metal beinghandled.

As will be apparent generally from Figure 1, there is a cross conveyormechanism 2t effective for transferring material from the conveying unit2 to the curling units l9. In FigureA of the drawings this crossconveyor mechanism is illustrated as comprising a, series of suitableguides in each of which is adapted to travel from a position in linewith the conveying unit to a position adjacent the curling units, apusher 22 carried on suitable rolls or wheels 22 and including pusherdogs 25 and 25.

It may be assumed by way of illustration that a piece of material M tobe formed into a tube has passed through the forming unit 5 and has beendelivered by the conveying unit to theposition illustrated in chainlines in Figure 4. In this position, an operation of the pusher 22 tothe left will move the material from a position over the conveying unitto a position adjacent the conveying unit and intermediate the same andthe curling units l9, as indicated at M in Figure 4:. Upon a returnmovement of the pusher 22 intothe full line position illustrated inFigure 4, each dog 25 will rotate about its pivotal mountings and passfreely under the next piece of material M on the conveying unit. Upon a.succeeding movement ofthe pusher 22 to the left as viewed in Figure 4,the dogs 24'on the respective .pushers will engage the material M andmove it into the curling units,

while the dogs 25 will move a piece of material M from the conveying.unit into the position M. Upon the next return movement, the dogs 2dwill pivot and pass freely under the material M, while the dogs. 25 willpivot and ,pass freely under the next piece of material M, if inposition on the conveying unit. In most cases, however, the second pieceof material will not arrive in the position M shown in Figure 4 untilafter the piece has been moved from position M' into the curling units.a

The operation of the pusher 22 is obtained by means of suitableoperating links 26 operatively connected atone end to the pusher 22 ineach of the guides 2|, and operatively connected at their other ends toan oscillating shaft 21. This shaft is conveniently joumaled in suitablebearings in the curling units l9, and may be operated in any desiredmanner for effecting the requisite movements of the pushers 22. Inasmuchas these pushers are all secured to'the same. shaft, it is apparentthatthey will operate in unison upon each movement of the shaft, and therebyexert a. simultaneousand distributed feeding action/on the material.

As will be apparent. more particularly from Figures 4, 5 and 6 cf thedrawings, each of the units comprises a base 28 of suitable constructionproviding a. pivotal mounting 29 about which the upper housing section30 is openable from the full line position of Figure 4 to the full lineposition of Figure 6. In this opened position, the upper a pair ofshaping shafts and 36, of generally similar construction. These shaftsin all of the curling units are mounted in suitable bearings 31 in eachof the curling units, as indicated for example in Figure 5, the bearingsbeing adjustable vertically by means of suitable wedge adjustingmechanism 38. Carried by shaping rollers 35 and 3511s a mandrel 39, alsoextending through the various curling units and common thereto.

For preventing e'ndwise movement of the mandrel 39 relatively to theshaping shafts 35 and 36, the mandrel is provided with a collar 40(Figure 5) adapted to interflt with suitable grooves 6| in the drivingspindles 42 for the shaping shafts. Due to this construction, when theupper housing sections 30 are thrown to their open position asillustrated. in Figurefi, access to the mandrel may be freely had, andthe mandrel bodily removed. Suitably journaled in the upper housingsections is a. backing up roll or shaft 43 adapted with thehousing-sections in closed position to overlie the mandrel 39. Thebacking up shaft 43 is in turn backed up in each of the curling units bya pair of independent rollers M. Also carried by each of the housingsections 30 is a die 415, the various dies being of such length as toabut end for end,

as shown in Figure 2 and thereby provide a con- 4 tinuous die surface ashereinafter more fully pointed out.

The shaping shafts 35 and 3B are adapted to be driven through suitablespindles and 47 respectively, each spindle including universal' jointsand adjustable couplings 38. By reason of the adjustability .of thecouplings 38, it is possible to properly index the shaping shafts 35 and36 to bring them into the desired cooperative relationship one to theother and to the other parts of' housing contains an intermediate gear5| carried by a shaft 52 adapted to be driven through a suitable geartrain 53 and motors 54. Meshing with the gear 5| is a similar gear 55 ona shaft 56, which shaft is operatively connected to the spindle 41. onthe opposite side of the gear 5| is a second gear 51on a shaft 58constituting the driving means forthe spindle 46, while above the gear5| is a gear 59 on a shaft 60 constitut ing the driving meansfor thebacking up spindle 49. For purposes which will hereinafter be more fullyset forth, the operative connectionv be- --tween the gear 55 and theshaft 56 includes a pawl 6|, while asimilar pawl. constitutes anoperative connection between the gear 61 and its shaft 58. v

In Figure 15 the direction of rotation of each of the parts is indicatedby suitable arrows. By reason of the pawls 6| and 62, the gears 55 and5'l when rotating in a clockwise direction as viewed in Figure 15 and asindicated by the arrows, will transmit rotation to the respective shafts56 and 56, but the shafts may move ahead relative to the gears in casethe drive for the shaping shafts and, 36is transferred from the spindles46 and 41 to some other portion of the apparatus.

In Figure 7, we have indicated one edge of a piece of material M whichhas been advanced by the pushers .22 into a position between the mandrel39 and the backing up shaft 43 with its front edge against the die 45.Rotation of the parts will cause the leading edge to gradually curldownwardly over the shaping surface of the individual die sections 65,and between the same and the mandrel 39, as indicated in Figure 8, thisoperation continuing as indicated in Figure 9.

Further rotation will bring the parts into'the relative positionillustrated in Figure 10, wherein the leading edge 63 of the material isabout to engage a shoulder 64 on the shaping shaft 35. In Figure 11 thisengagement has been effected and the material has been advanced into aposition between the mandrel 39 and the shaping shaft 35. Up until thetime that the leading edge 63 of the material engages the shoulder 64,the periphery of the shaping shaft 35 at its portion of maximum diameteris in engagement with the mandrel 39. After this engagement, theeifective radius of the mandrel 39 is increased by the thickness of thematerial so that the peripheral speed of the mandrel plus the material,or the peripheral speed of the outer surface of the material is greaterthan the peripheral speed of the mandrel itself. Thus, with the parts inthe position illustrated in Figure 11, the mandrel tends to rotate theshaping shaft 35 faster than it is driven by the gear 51. Therefore, theshaft 35 tends to drive the shaft 58 in a clockwise direction as viewedin Figure 15 ahead of the gear 51, which relative movement is permittedby the pawl 62.

Continued rotation of the parts brings the leading edge 63 out ofengagement with the shoulder 64 on theshaft 35 and into engagement witha shoulder 65 on the shaft 36. with the parts illustrated in the,position of Figures 10 and 11, the portion of maximum diameter of theshaft 36 is in driving engagement with the mandrel 39, but when theparts reach the position of Figure 12 and the effective radius ofthemandrel 39 is increased, the shaft 36 tends to moveahead of relativemotion being permitted by the pawl 6|.

Continued rotation will bring the parts into the position of Figure 13wherein the material is completely formed around the mandrel with theadiacent edges thereof in opposed relationship and accommodated by alongitudinally extending depression 61 in the backing up shaft 43. Theedges naturally tend to spring apart to some extent and unless thegroove 61 were provided, there might be a binding action between thematerial. the mandreland thebacking up shaft 43 which would preventendwise stripping of the blank from the mandrell The slight springingapart permitted by the depression, however, loosens the blank from themandrel, as indicated inFigure 13, sothat it may be stripped axiallytherefrom.

In Figure 4, we have illustrated the stripper as comprising an arm 66which extends inwardly 5 toward the mandrel and has its inner endcontoured to substantially conform to the periphery of the mandrel. Atits extreme outer end it is carried by a guide rod 69, as shown moreparticularly in Figure 2, guided in lugs 16 project- 10' ing outwardlyfrom a cylinder H. The piston rod 12 of the cylinder engages thestripper .68 intermediate its inner end and the guide rod 69. Uponadmitting fluid to the stripper cylinder 1|, the'stripper will be movedto the left as viewed 15 in figure 2. During this time its inner endwill be in engagement with the end of the blank and the blank will thusbe stripped endwise of the mandrel, bringing its left hand end as viewedin Figure 1 into the pass of a sizing unit I3 illus- 20 trated in detailin Figure 14; a f

This sizing unit conveniently comprises a series of rolls I4, hereinillustrated as being four in number, providing a substantially enclosedpass around inner shaping rolls 15 carried by a man- 25 desired sizingpressure may be exerted on the its driving shaft 56 for reasonsdescribed, this blank for accurately crushing the same to the desiredcontour and accurate diameter. After moving through the sizing unit 13,it maybe stripped from the mandrel 16 in any desired manner andsubjected to any further operations, such for example as a weldingoperation for completing the blank into a tube, pipe, or conduit or thelike.

Since the apparatus includes a plurality of curl- 5 ing units arrangedin side by side relationsh p; with sectional dies, the dies may bereplaced individually as required to insure the maintenance of anaccurate forming surface. Since all of the curling units aresimultaneously operable on 0 a blank throughout substantially its entirelength, the curling up operation may be accomplished without anytendency to impart a camber to the blank. At the same time, theshoulders 64 and 65 on the shaping shafts 35 and 36 55 constitute apositive guide means for the leading edge 63 of the material preventingit from twisting around .the mandrel '39. In the absence of anytwisting," the edges will be brought into. opposed relationship asillustrated in Figure 13 60 along a substantially straight line freefrom any discernible spiral.

The provision of the indexing adjustments 48 in the spindles l6 and '41enables the position of the shoulders 66 and 65 to be properlyinitially- 55 positioned one with respect to the other so that they willconstitute edge engaging means and guiding means for the material beingshaped into a blank.

The simultaneous curling of a blank through- 7 out its entire lengthinto a tube of standard dimensions, while accurately controlling theposition of' the blank, constitutes an important advantage of ourinvention by reason of the superior product thereby obtainable. 75

made without departing either from the spirit of our invention or thescope of our broader claims.

We claim: 1. Tube forming means, comprising a mandrel,

' a shaping shaft cooperating therewith and having portions of differentdiameters, and means for driving the shaping shaft, said means including a connection permitting the shaping shaft to move at a speed equalto or greater than the speed of the driving means.

2. Tube forming means, including a mandrel, a shaping shaft, and abacking up shaft, said backing up shaft having a depression adapted toreceive the meeting edges of a blank formed around the mandrel.

3. Tube forming means including a mandrel, a shaping shaft, a backing upshaft, said backing up shaft having a depression adapted to receive themeeting edges of a blank formed around the mandrel, and means forstripping a blank from said mandrel.

4. In a tube forming apparatus, a mandrel, means for feeding materialaround the mandrel, and a shaping shaft cooperating with the mandrel,said shaft having shoulders extending longitudinally thereof,substantially equal in height to the thickness of the material,providing an annular space for receiving successive portions-of thematerial as it is bent around the mandrel, to maintain shaping pressurebetween the mandrel and shaft with a fixed spacing of their axes.

5. Tube forming means comprising a. mandrel and a shaping shaftcooperating therewith forof substantial thickness around bending a platethe mandrel while passing between the mandrel and shaft, said shafthaving a raised peripheral shoulder extending longitudinally,substantially equal in height to the thickness of the plate, forengaging the mandrel before entry and after passage of the plate betweenthe mandrel and s a t.

6. Tube forming means, comprising a mandrel, means for feeding materialaround the mandrel, ashaping shaft supporting the mandrel, and mmgitudinally extending shoulders on the shapi shaft providing a passbetween the mandrel and shaft for receiving the material while beingbent around the mandrel and maintaining a fixed spacing of the axes ofthe mandrel and shaft be-- fore entry and after passage of the materialtherebetween.

7. The apparatus defined by claim 5 characterized by means for feedingthe plate longitudinally into side-by-side relation with said tubeforming means, and means for moving the plate laterally into the tubeforming means.

8. The apparatus defined by claim 5 characterized by a plurality ofspaced, individually removable bending dies cooperating with themandrel.

9. The apparatus defined by claim 5 characterized by the fact that thetube forming means another of said sections, the

comprisesv a series of alined bending units, each including a separablebending die, the mandrel and shaping roll being common to all saidunits. 10. The apparatus described by claim 5 characterized by means foradjusting the position of 5 the shaping shaft relative to the mandrel.

11. The apparatus defined by claim 5 characterized by a drive for saidshaping shaft, and means for adjusting the position of the shaping shaftrelative to said driving means.

12. Tube forming means comprising a unit for curling metal plate, theunit having a mandrel and a shaping shaft cooperating therewith, the

mandrel and the shaft being rotatable I about axes spaced asubstantially fixed distance apart, the shaping shaft having a sector ofsuch radius that the peripheral surface of the sector lies insubstantial engagement with the peripheral surface of the mandrel whensuch sector is presented to the mandrel by rotation of the shaft, theshaft having anothersector of smaller radius, the difference in radii ofthe two sectors being substantially equal to the thickness of the metalplate to be curled, whereby the last mentioned sector, when-presented tothe mandrel by continued rov tation of the shaft, has its peripheralsurface spaced from the peripheral surface of the mandrel a distancesufficient to accommodate the metal plate being worked, thelast-mentioned sector being of sufficient peripheral length toaccommodate the successive portions of the plate as it is fed betweenthe mandrel and the shaft.

13. Tube forming means as defined in claim 12, characterized by aplurality of curling units of the character referred to, the mandrel andshaping shaft being common to all of said units.

14. Tube forming means as defined in claim 12, characterized by drivingmeans for the shaping shaft including a releasably engaging connectionto 'permit the shaping shaft to move at a speed 40 greater than thespeed at which it is positively driven.

,15. Tube forming means as defined in claim 12, in which the curlingunit includes openable sections, a backing up shaft carried by one ofthe sections, the shaping shaft being carried by another-of thesections.

16. Tube forming means as defined in claim 12, in which the curling unitincludes openable sections, a backing up shaft carried byone of thesections, the shaping shaft being carried by another of the sections,the mandrel being rotatably supported at least partially by said shapingshaft.

17. Tube forming means as defined in claim 12, in which the curling unitincludes openable sections, a backing up shaft carried by one of saidsections, a plurality of shaping shafts carried by mandrel beingrotatably supported on said shaping shafts, and 60 means on the shapingshafts for holding the znandrel against axial movement relativelythereo. v LORENZ IVERSEN.

CHARLES L. RAISIG.

